The present invention relates to a method of encoding alphabetic characters for a chord keyboard. More specifically, the present invention relates to a method of encoding alphabetic characters for a chord keyboard and generating electrical signals identifying the alphabetic characters to a word processor or the like.
Chord keyboards are known in the art and generally include at least five character keys, one for the thumb and each of the four fingers of a single hand of an operator. These chord keyboards are designed so that keys may be actuated either individually or in chord combinations to selectively generate the 26 letters of the English alphabet. In order to make these chord keyboards practical, the codes or conventions for generating the alpha characters should be easy to learn and remember. Chord keyboards of the type described are disclosed in U.S. Pat. Nos. 4,443,789 and 4,360,892 to Endfield. Another example of such a keyboard is described in U.S. Pat. No. 4,791,408 to Heusinkveld.
Attempts have been made to simplify the encoding of a chord keyboard for ease of learning and memory. Endfield for example in the above-described patents discloses a visual method for facilitating ease of learning and memory whereby the various chord combinations of the alpha key actuations are intended to visually illustrate pictographs of the letters which the chords represent. While this method of learning the chord combinations may be a step in the right direction, it falls far short of providing a simple learning technique for the chords. Accordingly, a need in the art exists for an improved method for encoding the alphabetic characters of a chord keyboard which is learnable.